A vehicle barricade is a device which is disposed across a roadway in order to control passage along the roadway. The barricade normally has a barrier plate which is pivotal between a first lowered position, permitting passage along the roadway, and a second raised position, preventing passage. Naturally, there are suitable operating mechanisms, such as hydraulic cylinder and piston assemblies, for pivoting the barrier plate between the positions. An illustrative aboveground barricade is illustrated in my prior U.S. Pat. No., 4,574,523, for Vehicle Barricade or Maximum Security Barrier, issued Mar. 11, 1986.
My prior above cited patent discloses an above-ground barricade suitable for many installations. Some locations, on the other hand, may not wish to have an above-ground barricade for aesthetic or structural reasons. Belowground barricades are known, but most require extensive preparatory excavation and do not adequately withstand the impact force of the onrushing vehicle.
Those skilled in the art understand that there is a need for a belowground barricade which can be installed with minimal amount of excavation, in a minimal time period, and which assures positive transfer of the impact forces to the barricade structure in order to assure integrity of the barrier plate upon impact. The disclosed underground barricade is one meeting these criteria and which is of lightweight construction while retaining maximum strength.